Background and aim: Direct posterior reduction and manipulation of the C1-2 joints, accompanied by placement of spacers, is the state-of-the-art technique for treating basilar invagination (BI) and atlantoaxial dislocation (AAD). The hindrance of occiput to reaching up to the true atlantoaxial facets (AAF) during the surgery remains challenging for cage placement. The aim of this study was to explore an objective and precise method of measuring the effect of the hindrance of occiput to reaching up to the true AAF and cage placement during surgery. Method: We collected the clinico-imaging data of 58 patients with BI and AAD (Group A) who underwent surgery in our hospital, and 78 control cohorts (Group B) were retrieved retrospectively. We measured facet-occiput slope angle (FOSA) in midsagittal CT. Patients were positioned prone for surgery based on preoperative flexion O-C(2)a, and access to the true AAF was observed intraoperatively. The cut-off value of FOSA for the feasibility of cage placement in BI and AAD patients was appointed when access to the true AAF was impossible due to the hindrance of occiput during surgery. Results: The cut-off value of FOSA for the feasibility of cage placement was 34 degrees with an area under the curve AUC of 0.800 (95 % CI: 0.672-0.928, P < 0.001) and the Youden index of 0.607. In patients with FOSA >34 degrees, reaching up to the true AAF and 3D-printed cage placement was impossible. FOSA was negative in Group A and positive in Group B, significantly larger in females compared to males in both groups and significantly larger postoperatively in Group A. Conclusion: FOSA can objectively measure the feasibility of cage placement when the patient is positioned prone per preoperative flexion O-C(2)a. A FOSA >34 degrees is contraindication for cage placement.

The present study aimed to explore the role of histone chaperone anti-silencing function 1B (ASF1B) in pancreatic cancer and the underlying mechanism. The biological function of ASF1B was investigated in pancreatic cancer cell lines (PANC-1 and SW1990) and a mouse xenograft model. Chromatin immunoprecipitation was used to detect the effect of ASF1B on the transcriptional activity of c-Myc. ASF1B was highly expressed in pancreatic adenocarcinoma (PAAD) samples from The Cancer Genome Atlas. ASF1B expression was positively associated with poor survival rates in patients with PAAD. Silencing of ASF1B in PANC-1 and SW1990 cells inhibited cell proliferation, migration and invasion, and induced apoptosis. Mechanistically, ASF1B increased H3K56 acetylation (H3K56ac) in a CREB-binding protein (CBP)-dependent manner. ASF1B promoted H3K56ac at the c-Myc promoter and increased c-Myc expression. In PANC-1 and SW1990 cells, the CBP inhibitor curcumin and the c-Myc inhibitor 10058-F4 reversed the promoting effects of ASF1B on cell proliferation, migration and invasion. In the mouse xenograft model, ASF1B silencing inhibited tumor growth, and was associated with low H3K56ac and c-Myc expression. ASF1B promoted pancreatic cancer progression by activating c-Myc via CBP-mediated H3K56ac.

With the aim of improving the prognosis of patients with lung adenocarcinoma (LUAD), we identified the biomarker related to the sensitivity of patients to chemotherapy drugs and explored the potential mechanisms. As a cell cycle-related protein, CKS2 has an essential role to play in tumor progression and prognosis. CKS2 expression was measured using TCGA RNA-sequencing data and immunohistochemistry. The sensitivity data of tumor cells to chemotherapeutic drugs for lung cancer was acquired from the Cancer Therapeutics Response Portal (CTRP) database. A range of bioinformatics methods was used to explore the mechanisms of CKS2 upregulation. The biological functions of CKS2 were predicted using GO and KEGG enrichment analysis, as well as GSEA. CKS2 expression was up-regulated in stages I–III invasive non-mucinous lung adenocarcinoma and varied significantly between various histological subtypes. High CKS2 expression worsened the prognosis of patients. The CKS2 expression level was linked to the sensitivity of LUAD cells to carboplatin and paclitaxel. CKS2 upregulation was associated with the immune microenvironment, mRNA methylation, and competing endogenous RNAs (ceRNAs). CKS2 can serve as a diagnostic and prognostic biomarker for stages I–III invasive non-mucinous lung adenocarcinoma and modulate the effect of paclitaxel and carboplatin by regulating microtubule binding and influencing carboplatin binding to DNA.

OBJECTIVE: To investigate the efficacy of a lateral mass fusion device combined with a three-dimensional-printed model in treatment of craniovertebral junction abnormalities. METHODS: This retrospective study comprised 56 patients with irreducible atlantoaxial dislocation who underwent posterior fixation between January 2016 and December 2019. Patients were divided into 2 groups according to whether or not cages were used-cage group and autograft group. Visual analog scale score, Japanese Orthopaedic Association score, health-related quality of life, American Spinal Injury Association spinal cord injury grade, atlas-dens interval, space available for the cord, cervicomedullary angle, and fusion rate were compared between groups. RESULTS: Medical follow-up was >1 year. There was no statistical difference between groups in preoperative visual analog scale score, Japanese Orthopaedic Association score, 12-Item Short Form Health Survey score, American Spinal Injury Association grade, atlas-dens interval, space available for the cord, and cervicomedullary angle, and these indexes significantly improved after surgery (P < 0.05). Visual analog scale score and atlas-dens interval were lower in the cage group than in the autograft group (P < 0.05). Japanese Orthopaedic Association score, 12-Item Short Form Health Survey score, space available for the cord, and cervicomedullary angle were significantly higher in the cage group than in the autograft group (P < 0.05). Fusion rate of the cage group 4-6 months after surgery was higher than that of the autograft group (P = 0.068). American Spinal Injury Association grade was significantly higher in the cage group than in the autograft group (P < 0.05). CONCLUSIONS: During 1-year follow-up, neurological function improvement and atlantoaxial joint reduction were satisfactory. The lateral mass fusion device combined with a three-dimensional printed model may be a clinically useful technique.

Aims Considering morphological heterogeneity of lung adenocarcinoma (LUAD) and no objective prognostic grading system existing currently, we aim to establish an ‘optimised architecture-based grading system’ (OAGS) to predict prognosis for resected LUAD. Methods A multicentral study involving three independent cohorts of LUAD was conducted. Predictive ability of the OAGS for recurrence-free probability (RFP) and overall survival (OS) was assessed in training cohort (n=228) by the area under the receiver operating characteristic curve (AUC), Harrell’s concordance index ( C -index) and Kaplan-Meier survival analyses, which was validated in testing (n=135) and validation (n=226) cohorts. Results The OAGS consists of: grade 1 for lepidic, papillary or acinar predominant tumour with no or less than 5% of high-grade patterns (cribriform, solid and or micropapillary), grade 2 for lepidic, papillary or acinar predominant tumour with 5% or more of high-grade patterns, and grade 3 for cribriform, solid or micropapillary predominant tumour. In all stages, the OAGS outperformed the pattern-dominant grading system and IASLC grading system for predicting RFP (C-index, 0.649; AUC, 0.742) and OS (C-index, 0.685; AUC, 0.754). Multivariate analysis identified it as an independent predictor of both (RFP, p<0.001; OS, p<0.001). Furthermore, in pT1-2aN0M0 subgroup, the OAGS maintained its ability to predict recurrence (C-index, 0.699; AUC, 0.769) and stratified patients into different risk groups of RFP (p<0.001). These results were confirmed in testing and validation cohorts. Conclusions The OAGS is an independent prognostic factor and shows a robust ability to predict prognosis for resected LUAD.

PURPOSE:The International Federation of Gynecology and Obstetrics (FIGO) stage remains the standard staging system for the assessment of endometrial cancer (EC) prognosis. Thus, we aim to identify the significant genes or biomarkers associated with the stage of endometrial cancer, which may also help reveal the mechanism of EC progression and assess the prognosis of patients with EC.MATERIALS AND METHODS:We compared the mRNA expression levels of EC patients with stages I and II as well as stages III and IV in the Cancer Genome Atlas (TCGA) database. The differentially expressed genes (DEGs) of EC patients at different stages were selected by volcano plot and Venn analysis. Gene Ontology (GO) and Pathways were applied to analyze the identified genes. Protein protein interaction (PPI) network was employed to identify the correlation. The survival analyses based on TCGA database were conducted for further screening. The Human Protein Atlas, quantitative PCR and immunohistochemistry were utilized to confirm the differences in expression of DEGs in endometrial cancer samples at different FIGO stages.RESULTS:CKMT1A was identified as a candidate gene. Through survival analyses, we found that CKMT1A may be a poor prognostic factor in the overall survival of endometrial cancer patients. GO and Pathways revealed that CKMT1A is closely associated with the metabolic process. More importantly, Human Protein Atlas and quantitative PCR confirmed the differences in expression of CKMT1A in endometrial cancer samples at different FIGO stages.CONCLUSION:In summary, this study shows that CKMT1A is a newly identified essential tumor progression regulator of endometrial cancer, which may give rise to novel therapeutic strategies in the management of endometrial cancer patients to prolong its prognosis and prevent tumor progression.

Nanoparticles possess the ability to adsorb and load other compounds. This study aimed to synthesize a gene carrier with polyethyleneimine (PEI), hyaluronic acid (HA) and mesoporous silica nanoparticles (MSNs) for circ_0086375 delivery to investigate the role and mechanism of circ_0086375 in pancreatic cancer (PC) progression. The expression of genes and proteins was detected by quantitative real-time polymerase chain reaction and Western blot. In vitro experiments were performed by cell counting Kit-8 (CCK-8), 5-Ethynyl-2′-deoxyuridine (EdU) assay, flow cytometry, transwell assay, and wound healing assay, respectively. Dual-luciferase activity assay was used to investigate the target relationship between miR-646 and circ_0086375 or SLC4A4 (solute carrier family 4 member 4). Circ_0086375 loaded PEI/HA-based mesoporous silica nanoparticles (MSNs) were prepared, and in vivo assay was performed by using xenograft tumor model. Circ_0086375 expression was decreased in PC tissues and cells. Restoration of circ_0086375 suppressed PC cell proliferation, migration and invasion in vitro and in vivo. Mechanistically, circ_0086375 acted as a sponge for miR-646 to elevate SLC4A4 expression, which was confirmed to be a target of miR-646. The prepared circ_0086375/MSN/PEI/HA nanocomplexes showed excellent fluorescent properties and a higher cellular uptake of circ_0086375 in PC cells. Moreover, circ_0086375/MSN/PEI/HA showed relatively more anticancer effects in PC than that of circ_0086375 alone in vitro and in vivo. Delivery of circ_0086375 by nanoparticles suppresses the tumorigenicity of pancreatic cancer by miR-646/SLC4A4 axis, suggesting a new potential target for future pancreatic cancer treatment.

Objective: For investigating Dbx2's expression in endometrial cancer (EC) and its effect on prognosis of patients with EC. Methods: A comparison was performed in the Cancer Genome Atlas (TCGA) database in terms of the expression profiling of EC and the survival data. To obtain differential expression genes (DEGs), Volcano plot and Venn analysis were adopted. DEGs function was performed by carrying out the GO annotation analysis (GO) and gene set enrichment analysis (GSEA). In clinical EC samples, PCR was applied to the verification of Dbx2's expression. Results: Dbx2 was a downregulated expression in tumor tissues. Dbx2 can have a poor prognosis role in EC by regulating the apoptotic signaling pathway and the immune pathway. Lower expression of Dbx2 was related to lymph node metastasis and FIGO stage. Conclusion: Dbx2 is downregulated in endometrial cancer, which serves as a biomarker to predict poor prognosis.

Long non-coding RNAs (lncRNAs) have been noted to influence the progression of ossification of posterior longitudinal ligament (OPLL). The work aims to probe the effect of lncRNA SNHG1 on osteogenic differentiation of ligament fibroblastic cells (LFCs). Aberrantly expressed lncRNAs in ossified PLL tissues were screened out by microarray analysis. Gain- and loss-of function experiments of SNHG1 were performed to identify its role in osteogenic differentiation of LFCs. The downstream molecules of SNHG1 were explored. Altered expression of miR-320b was introduced in LFCs as well. The interactions among SNHG1, miR-320b and IFNGR1 were identified. Consequently, SNHG1 was found highly expressed in OPLL patients. Silencing of SNHG1 inhibited BMP-2, RUNX2 and OCN expression and the ALP activity and reduced osteogenic differentiation of LFCs. Importantly, SNHG1 could and upregulate IFNGR1 through serving as a sponge for miR-320b. Over-expression of miR-320b inhibited osteogenic differentiation of LFCs and inactivated the JAK/STAT signaling pathway. Further administration of Fedratinib, a JAK2-specific agonist, increased osteogenic differentiation of LFCs. To conclude, the study suggested that SNHG1 could upregulate IFNGR1 by sequestering miR-320b and activate the JAK/STAT signaling. Silencing of SNHG1 could reduce the osteogenic differentiation and mineralization of LFCs. The study may offer new insights into OPLL treatment.

Objective Histology grade, subtypes and TNM stage of lung adenocarcinomas are useful predictors of prognosis and survival. The aim of the study was to investigate the relationship between chromosomal instability, morphological subtypes and the grading system used in lung non-mucinous adenocarcinoma (LNMA). Methods We developed a whole genome copy number variation (WGCNV) scoring system and applied next generation sequencing to evaluate CNVs present in 91 LNMA tumor samples. Results Higher histological grades, aggressive subtypes and more advanced TNM staging were associated with an increased WGCNV score, particularly in CNV regions enriched for tumor suppressor genes and oncogenes. In addition, we demonstrate that 24-chromosome CNV profiling can be performed reliably from specific cell types (<100 cells) isolated by sample laser capture microdissection. Conclusions Our findings suggest that the WGCNV scoring system we developed may have potential value as an adjunct test for predicting the prognosis of patients diagnosed with LNMA.

BACKGROUND: The Hoffmann sign is usually used as an indicator of upper motor neuron lesion, but its clinical effect remains controversial in previous reports. METHODS: A retrospective case control study including 107 patients with cervical complaints was carried out. According to the presence of Hoffmann sign, patients were divided into 2 groups. The radiographic results were assessed and the sensitivity, specificity, positive and negative predictive values, and false positive and false negative values of Hoffmann sign for cervical pathology, segment, cervical spine canal ratio, and S-index were calculated. RESULTS: There were 56 patients in the positive Hoffmann group and 51 patients in negative group. The sensitivity, specificity, positive and negative predictive values, and false positive and false negative values of Hoffmann sign for cervical pathology were found to be 61.6%, 85.7%, 94.6%, 35.3%, 14.3%, 38.4% and 60.5%, 81.0%, 92.9%, 33.3%, 19.0%, 39.5%, respectively. The ratio of cervical spine canal was lower in the positive Hoffmann group than in control group. CONCLUSIONS: Although the Hoffmann sign is not foolproof in the diagnosis of cervical spinal cord compression, it can be used to assess symptomatic patients. The narrower the cervical spine canal or the higher the cervical segment compression, the higher of the incidence of positive Hoffmann sign.

Purpose According to the WHO, the cribriform pattern is a subtype of acinar (Aci) predominance in invasive adenocarcinoma (ADC) of the lung. Recently, several studies have demonstrated poor prognosis in patients with cribriform predominance. This study was performed to examine the correlations of cribriform pattern with the clinicopathology, molecular features and prognosis in patients with invasive ADC. Methods Histological subtypes were evaluated in 279 patients who underwent complete resection for invasive ADC. Patients of the Aci-predominant subtype were divided into two subgroups according to the percentage of cribriform cancer (>= 5% vs <5%). Clinicopathological characteristics, overall survival (OS), disease-free survival (DFS) and molecular changes were compared. In addition, both OS and DFS were compared between patients with cribriform-predominant (n=33) and pure Aci-predominant (n=88) ADCs. Results A cribriform pattern was found in 111 (39.8%) cases and ranged from 5 % to 100 % of the total tumour volume (mean +/- SEM, 30%+/- 2%). Of 117 patients with Aci predominance, 79 showed the cribriform pattern, while the remaining 38 did not. The cribriform pattern was associated with aggressive pathological behaviour, including advanced stages of cancer, nuclear atypia, mitoses, lymph node invasion, metastasis and larger tumour size. The subgroup with cribriform cancer (>= 5%) had significantly poorer OS and DFS compared with the cribriform-negative (<5%) group. In addition, Cox multivariate analyses revealed that the cribriform pattern was an independent predictor of OS but not DFS. Moreover, OS was significantly lower in the cribriform-predominant group than in the Aci-predominant group. Conclusion The cribriform pattern is associated with aggressive pathological behaviour and is an independent poor prognostic indicator in patients with Aci-predominant ADC of the lung.

Objective To establish a preliminary model which can effectively predict the risk for postoperative delirium (POD) in elderly orthopedic patients and verify its effectiveness.Methods This prospective study involved 2 cohorts.For an analysis cohort,the assessment data of 148 elderly orthopedic patients were collected who had been treated at Department of Orthopaedics,the First Affiliated Hospital of Zhengzhou University from June to October 2017.The relevant risk factors for POD (gender,age,BMI,schooling ＜ 9 years,history of smoking and alcohol drinking,concomitant diseases and perioperative factors) were screened after comparing POD and non-POD patients.All the risk factors were analyzed and a predictive model was established after valuation of independent risk factors.A predictive cohort of 66 patients was included according to the same inclusion and exclusion criteria as the analysis cohort out of the patients who had been treated at our hospital from November to December 2017.The 2 cohorts were scored by the predictive model to verify the validity of the model.Results A total of 18 risk factors were identified in this study.In the analysis cohort,age (P =0.006),schooling ＜ 9 years (P =0.043),cerebrovascular disease or mental illness (P =0.004),preoperative albumin (P =0.038) and intraoperative infusion of allogeneic blood (P =0.019) were risk factors for POD.Of them,age (P =0.037),schooling ＜ 9 years (P =0.003) and intraoperative infusion of allogeneic blood (P =0.042) were independent ones.In the predictive model,age ＞ 75 years was assigned 3 points,schooling ＜ 9 years 2 points and intraoperative infusion of allogeneic blood 5 points.The validity of the ROC curve was verified for the predictive model.According to the ROC curve,the analysis cohort had AUC =0.66 and the predictive cohort AUC =0.75,indicating a certain predictive value of the model.Conclusion Our predictive model can be used to effectively screen out those with a high risk for postoperative delirium from elderly orthopedic patients.

Objective To investigate the role of ATRX and P53 gene mutations in the classification of diffuse glioma in Chinese. Methods A total of 89 cases of diffuse astrocytoma (IDH mutation) or diffuse astrocytoma (IDH wild type) and all levels of oligodendroglioma from 2016 to 2017 were collected, and detected the expression of ATRX protein and over expression of P53 protein by immunohistochemistry, and analyzed their expression in different types of diffuse gliomas. Results The ratio of ATRX loss expression in diffuse astrocytoma (IDH mutation) (17/24) was higher than that in oligodendrogliomas (3/16), P<0.01; the ratio of P53 over expression in diffuse astrocytoma (IDH mutation) (15/24) was higher than that in oligodendrogliomas (1/16), P<0.01; the ratio of ATRX loss expression in diffuse astrocytoma (IDH mutation) (71%, 17/24) was higher than that in diffuse astrocytoma (IDH wild) (41%, 20/49), P<0.05. Conclusions ATRX and P53 mutation is one of the molecular genetic characteristics of diffuse astrocytoma (IDH mutation), which may be contributed to diagnose diffuse astrocytoma. Key words: Diffuse glioma; Tumor suppressor protein P53; Alpha thalassemia/mental retardation syndrome-X

Study Design. Prospective study. Objective. To analyze the most feasible choice of C1 lateral mass (C1LM) and C2 pedicle (C2P) screw in upper cervical surgeries for children younger than 6 years. Summary of Background Data. The C1LM and C2P screw technique is a stable cervical vertebrae internal fixation method in upper cervical surgery. Some tomographic studies have indicated the feasibility of insertion of C1LM and C2P screws in children. Their results, however, varied widely, and no consensus was achieved regarding C1LM and C2P screw choices for different ages in the pediatric population, sex, and laterality. Methods. The computed tomography images of 250 patients (age 2–6 yr) were studied. The inner diameter and length for each C1LM and C2P were measured in axial view. Height was measured in sagittal view. Screw choice was considered feasible when a sample maintained an additional 0.5 mm bone cortex at the inner diameter, length, and height at the same time. Analyses with the Student t test were performed for age, sex, and laterality. The screw choice was evaluated with a feasibility percentage. Results. Statistical differences were found between different ages, sex, and laterality for C1LM length (P < 0.001) and C2P length (P < 0.001). Screws of different sizes were recommended for each age group, sex, and laterality, with a feasibility percentage. Conclusion. The use of a 3.5-mm lateral mass and pedicle screw in 2- to 6-year-old children was feasible in the majority of cases. Age, sex, and laterality should all be considered when choosing screw sizes in pediatric upper cervical surgeries. This information can be particularly helpful for preoperative planning for C1-C2 internal fixation. Level of Evidence: 3

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a form of temporary mechanical circulatory support commonly used during cardiothoracic interventions. Malperfusion during complex vascular procedures remains a significant risk that may potentially lead to multiple complications. Here, we report two cases highlighting the efficacy of VA-ECMO in both planned and emergent vascular interventions.In our first case, VA-ECMO was used to support an 82-year-old male during a high-risk thoracoabdominal aortic aneurysm repair. Our second case details an emergent pulmonary embolectomy in which VA-ECMO was used as a bridge to cardiopulmonary bypass. In both cases, the procedures were well-tolerated, and the patients were discharged 17 days postoperatively.VA-ECMO has been increasingly used as a form of post-operative circulatory support following cardiothoracic and vascular interventions. However, only few instances of perioperative VA-ECMO use have been reported in the field of vascular surgery.The presented cases highlight that the perioperative use of VA-ECMO may be a viable modality for required perfusion during complex planned or emergent vascular procedures.

Objective To evaluate the clinical efficacy of transoral approach for atlantoaxial joint plasty with operating microscope.Methods Between June 2009 and July 2011,17 patients with various kinds of irreducible atlantoaxial dislocation were treated by the method of transoral for atlantoaxial joint plasty with the microscope and video output system under the direct vision.The operations of the process were in the real-time video and video output.Results All the operative processes were all right.By the video output system assembly,15.1 million pixels high-definition images could be collected and reached 1920 × 1080 pixels vidio camera.All the patients were followed-up for average 33 months(27 to 52 months).Neurological recoverywas significantly improved in 16 cases and took a turn for better in 1 case.The average JOA scores was increased from 8.1 ± 3.5 to 15.1 ± 1.8 at 2 years follow-up.According to Hirabayashi the average improvement rate was 78.7％,and 12 cases were classified as excellent and 5 as good.The cervico-medullary angle was increased from 128.6° ± 8.5° to 151.7° ± 10.4°.All patients gained solid bony fusion with a good alignment of C1 and C2 that were evaluated with postoperative plain X-rays and CT.At 12 months after operation,bony fusions were achieved.Conclusion Atlantoaxial joint plasty is one safe and effective method of managing patients with various kinds of irreducible atlantoaxial dislocation by transoral approach.The miscroscope can improve the safety of surgery.

Objective To observe the expression of calcitonin receptor in osteosarcoma cells and explore the factors influencing the development or prognosis of osteosarcoma.Methods Thirty-five cases of osteosarcoma specimens (23 cases in well-differentiated osteosarcoma group,and 12 cases in poorly differentiated osteosarcoma group) were designed as observation group.Ten cases of normal bone tissues served as control group.All the tissues were stained by streptavid-in-peroxidase (SP) method of immunohistochemistry to analyze the expression of calcitonin receptor.Results Positive rate of calcitonin receptor in osteosarcoma cells and normal bone tissues was 68.6％ and 30.0％ respectively (P ＜ 0.05).The expression rate of calcitonin in well and poorly differentiated osteosarcoma cells was 78.2％ (female:22.2％,and male:77.8％) and 33.3％ (female:50.0％,and male:50.0％) respectively (P ＜ 0.05).There was no statistically significant difference between two genders in different groups (P ＞ 0.05).Conclusion Positive rate of calcitonin receptor in osteosarcoma cells is higher than in normal bone tissues.What's more,the expression rate of calcitonin in well-differentiated osteosarcoma cells is higher than in poorly differentiated osteosarcoma cells.Calcitonin receptor may be related to grade malignancy and prognosis of osteosarcoma.

Objective To design and product a collimator for anterior cannulated odontoid screw by measuring the data of normal adult cervical spine from the images.Methods A total of 60 normal adults who received 64 row slice CT of the upper cervical spine and the X-Ray plain film of the cervical spine were chosen and divided into male and female groups.Statistical analysis was performed.Results The main anatomy parameters for the design of collimator were obtained.There was no significant difference in the disc height of the C2 and C3 anterior edge between 64 row slice CT [male:(3.26 ± 1.19) mm,and female:(2.54 ±0.83) mm] and X-ray [male:(3.2l ±0.78) mm,and female:(3.21 ±0.90) mm] in the lat-eral cervical spine (P ＞ 0.05).There was statistically significant difference in the length of C5 anterior lower edge midpoint corresponding skin straight pointing to the C2 front bottom edge midpoint between two groups [male:(89.09 ± 6.85) mm,and female:(75.93 ± 5.67) mm].Conclusion The collimator is designed for anterior canuulated odontoid screw.This collimator matching with human cervical anatomy is easier to be used in the clinical application.